ANALYSIS After a week of soul-searching and with a state investigation still looming, Sam Adams has decided to stick around as Portland's mayor.

Now comes the hard part.

The City That Works is in crisis, from the rising unemployment rate to the crumbling infrastructure to the mass shooting outside a downtown club Saturday night that left two people dead.

It's only been a week since Adams first admitted having sex with an 18-year-old legislative intern and then lying about it. But when Adams hits City Hall this morning, he'll be returning to a world transformed. The question is whether he can transform himself and his style to confront the new challenges.

"I know I've screwed up and let people down. But I still think I have a positive contribution to make," Adams told The Oregonian on Sunday. "I've learned some really important lessons, and I know I have to work hard to rebuild trust. All I can do is show up on Monday morning and start that process."

Adams called all four city commissioners early Sunday to let them know he had decided not to resign. He phoned before 9 a.m. with the same basic message for each: I'm coming back. I deserve due process. I hope we can still work together.

That remains to be seen.

"It was very short. I was half-asleep," said Commissioner Nick Fish. "I said I looked forward to getting back to work."

Fish wouldn't talk about what Adams must do to regain public trust.

"You should ask him that. I'm going to take a Sam-free day," he said. "I'm an elected official. I'm a professional. I have a job to do."

In 2007, as Adams was contemplating a run for mayor, rumors surfaced that he had a sexual relationship with Beau Breedlove, a former Oregon legislative intern, that may have begun when Breedlove was 17 and a minor.

Adams, now 45, fiercely denied the gossip and accused a potential political rival, real-estate developer Robert Ball, of spreading false rumors. He and Breedlove both said they were merely friends in a mentor-protege relationship. Breedlove said he had sought Adams' advice on being openly gay in politics.

But a week ago, prompted by new questions from Willamette Week, Adams admitted that he had lied and asked Breedlove to lie as well to protect his political career.

Over the past week, his story evolved. First, he said that he and Breedlove had sex several times after Breedlove's 18th birthday in June 2005 but that nothing "romantic" had occurred while Breedlove was still 17. Later, he said he and Breedlove had expressed some romantic attraction for each other before Breedlove's birthday and acknowledged that the "mentoring part" of their relationship was largely a lie.

On Saturday, Breedlove told The Oregonian that Adams kissed him twice before his 18th birthday, including once in a City Hall men's room.

That was the final straw for Commissioner Randy Leonard. He defended Adams in 2007, made some of the loudest complaints against Ball and began last week as Adams' closest ally on the City Council.

Their relationship is severely damaged.

"I think we're living in a fairly sane city that is caught up in some very crazy antics," said Leonard, who would have become mayor temporarily had Adams resigned. "I do not understand what he is possibly thinking at this point. I do not know how he comes back and expects to get anything done."

Supporters, who have been filling the Internet with petitions supporting Adams and objecting to newspaper editorials urging his resignation, celebrated Sunday.

As long as Adams and Breedlove didn't have sex before the younger man turned 18, they say, it's nobody's business. They say Adams, with his unique blend of policy-wonk smarts and poor-kid-made-good passion, is the best person to guide Portland out of this economic meltdown.

"I've tried to keep a clear focus on what this city needs, and that is leadership on tough issues," said John Russell, a developer and former chairman of the Portland Development Commission. "Over the years, he's shown a lot of vigor and class and fortitude. If he does that, we'll all move on."

But with the exception of Russell, City Commissioner Dan Saltzman and a few other business owners, the group that rallied for Adams last week included few of the corporate executives or elected officials he'll need to woo to be effective.

In interviews Sunday, more than a dozen movers and shakers said Adams must rethink his approach to the job and possibly scale down the scope of his vision to succeed.

What does that mean? No more showing up late for meetings, no more snarky asides to political opponents, no more hogging the camera at public events. (In his first public act since deciding to stay, Adams asked the Portland Bureau of Transportation to schedule a press conference so he could talk about Saturday night's snowfall. He quickly scuttled that idea when temperatures warmed.)

"It's not going to be easy for him," said James Hester, council representative for the American Federation of State County and Municipal Employees Council 75, city government's biggest union. "Assuming there are no other issues out there -- and I have to take him at his word on that -- there won't be room for any mistakes or lapses in his administration."

In terms of actual policy, Adams is going to have a hard time serving as "head cheerleader" for the public schools' attempts to cut the dropout rate. Sheer force of personality isn't going to be enough to build a convention center hotel or persuade his colleagues to use public money wooing Major League Soccer.

The risk is that disagreements over policy -- Adams and Leonard, for example, disagree on the size of the proposed new Interstate 5 bridge over the Columbia River -- will be made even worse by lingering mistrust and resentment.

"He's got to get back to work," said David Bragdon, president of the Metro Council. "It's as simple as that."

City Commissioner Amanda Fritz said she's ready to get back to work with Adams. "It is up to Sam to see if he can rebuild the trust which has been damaged, to allow him to be an effective leader," she said on her blog. The results of a state criminal investigation will determine if Adams should face sanctions, she said.

Adams has one thing working in his favor, besides a legendary work ethic and a core cadre of loyal and forgiving supporters: He has already remade himself once.

For 11 years, Adams served as Mayor Vera Katz's chief of staff, right-hand man and sometimes enforcer. He was uncomfortable in the public eye, largely quiet about his sexual orientation and unapologetically Machiavellian in his approach to solving his boss's problems.

The guy who ran for City Council in 2004 and mayor last year was quite different: charming and self-effacing, a smooth and eager public speaker, a missionary for government transparency and proudly, openly gay.

"This is going to be exceptionally difficult, but I think he knows that," said Katz, his mentor and surrogate mother. "This whole thing has been humiliating. It's been distracting. It's been unbelievable and unfortunate and his own fault. But he isn't running away."